The invention relates to an apparatus for ligation of affected part in coeloma, and more particularly to such apparatus which employes holding wires to facilitate and assure the formation of a loop.
An electric searing iron or electric coagulation member is used in a medical operation in order to remove a projecting affected part such as polyp formed in a coeloma, with the visual aid of an endoscope. However, the complexity and the safety of the instruments used present a problem in performing an operation with such instruments, and there is a risk that the removal of the affected part may result in a failure to stop bleeding. To overcome such difficulties, there has been proposed in Japanese Laid-Open Patent Publication No. 71,090/1973 the concept for a ligation of the root of the projecting affected part with a length of thread while controlling the operation by observing with an endoscope. The ligated tissue of the affected part is thus laid out of circulation of the blood to cause a necrosis for natural removal. This involves no risk of bleeding to thereby assure a safe operation, and also permits a specimen of the tissue to be picked as by forceps without involving danger. In this manner, the affected part can be safely treated.
A conventional ligature used in the prior art apparatus comprises a plurality of thin filaments twisted together, as shown in FIG. 1, so that when it is inserted into a forceps conduit of the endoscope or introduced into a coeloma, it becomes wetted by moisture or blood fluid present therein to be untwisted or disengaged as illustrated in FIG. 2. As a result, it is sometimes impossilbe to form a loop of the ligature which must be provided for engagement with and ligation of the affected part.
Additionally, a conventional ligation apparatus comprises a flexible tube having a loop formation merely exposed through the distal end thereof, which formation cannot be extended to a larger size. In addition, the loop configuration is not assured. As a consequence, it is extremely difficult, if not impossible, to engage the loop with the projecting affected part in the coeloma. Such a conventional ligation apparatus is illustrated in FIG. 15 and will be further described later.